Cleaning agent for PVC surfaces

Abstract

The invention relates to a method for adhesive bonding a PVC surface comprising cleaning a PVC surface with an aqueous alkaline cleaning composition and applying an adhesive to the cleaned PVC surface.

What is claimed is:  
     
       1. A method of adhesive bonding a PVC surface to a substrate, the method comprising: 
       cleaning a PVC surface with an aqueous alkaline composition comprising:  
       A) 2 to 30 wt. % of a compound different from complexing agent (B) and rinsing auxiliary agent (E) and having an alkaline reaction in an aqueous medium,  
       B) 1 to 30 wt. % of a complexing agent compound different from compound (A) and rinsing auxiliary agent (E),  
       C) 5 to 40 wt. % of a compound with at least one hydroxyl group selected from the group consisting of alcohols and ethers of alcohols wherein the alcohol contains 3 to 12 carbon atoms,  
       D) 1 to 15 wt. % of a surfactant based on fatty alcohols,  
       E) 1 to 30 wt. % of a rinsing auxiliary agent compound different from compound (A) and compound (B), and  
       F) 0 to 8 wt. % of water-soluble colorants and builders; and  
       applying an adhesive to either the cleaned PVC surface or the substrate and bonding the PVC surface and the substrate together.  
     
     
       2. The method of  claim 1  further comprising the step of pretreating the cleaned PVC surface prior to contacting the adhesive with the PVC surface. 
     
     
       3. The method of  claim 2  wherein the pretreating step is selected from the group consisting of flame treating the cleaned PVC surface, plasma radiation treating the cleaned PVC surface and corona treating the cleaned PVC surface. 
     
     
       4. The method of  claim 1  wherein the step of applying an adhesive comprises applying a moisture-reactive polyurethane melt adhesive. 
     
     
       5. The method of  claim 1  wherein the step of cleaning a PVC surface comprises contacting the PVC surface with the aqueous alkaline composition for a period of from about 1 second to about 30 minutes. 
     
     
       6. The method of  claim 1  wherein the step of cleaning a PVC surface comprises contacting the PVC surface with the aqueous alkaline composition at a temperature in the range of 10° C. to 80° C. 
     
     
       7. The method of  claim 1  wherein the compound with at least one hydroxyl group of component (C) of the aqueous alkaline composition is present at a concentration of 15 to 25 weight %. 
     
     
       8. The method of  claim 1  wherein the compound having an alkaline reaction in an aqueous medium of component (A) of the aqueous alkaline composition is selected from the group consisting of NaOH, KOH, waterglass, ammonia, amines, and mixtures thereof. 
     
     
       9. The method of  claim 1  wherein the compound having an alkaline reaction in an aqueous medium of component (A) of the aqueous alkaline composition is present at a concentration of 5 to 15 wt. %. 
     
     
       10. The method of  claim 1  wherein the aqueous alkaline composition has a pH above 12. 
     
     
       11. The method of  claim 1  wherein the aqueous alkaline composition has a pH of 13.5 to 14. 
     
     
       12. The method of  claim 1  wherein the complexing agent of component (B) of the aqueous alkaline composition is selected from the group consisting of Na salts or ammonium salts of diethylenetriamine pentaacetic acid, hydroxyethylenediaminetriacetic acid, propylenediaminetetraacetic acid, ethylenediaminetetraacetic acid, nitrilotriacetic acid, citric acid, alanine diacetic acid, polyaspartic acid, methylglycidine diacetic acid, polycarboxylates and mixtures thereof. 
     
     
       13. The method of  claim 1  wherein the complexing agent of component (B) of the aqueous alkaline composition is present at a concentration of 2 to 10 wt. %. 
     
     
       14. The method of  claim 1  wherein the compound with at least one hydroxyl group of component (C) of the aqueous alkaline composition is selected from the group consisting of benzyl alcohol, phenoxyethanol, propylene glycol n-butyl ether, propylene glycol methyl ether, propylene glycol isobutyl ether, propylene glycol phenyl ether, dipropylene glycol methyl ether, tripropylene glycol methyl ether, ethyl diglycols, methyl diglycols, butyl glycol, butyl diglycol, ethylene glycol and mixtures thereof. 
     
     
       15. The method of  claim 1  wherein the surfactant based on fatty alcohols of component (D) of the aqueous alkaline composition comprises fatty alcohols having 12 to 18 carbon atoms esterified with 3 to 50 ethylene oxide units, and, optionally 1 to 15 propylene oxide units. 
     
     
       16. The method of  claim 1  wherein the surfactant based on fatty alcohols of component (D) of the aqueous alkaline composition is present at a concentration of 2 to 8 wt. %. 
     
     
       17. The method of  claim 1  wherein the rinsing auxiliary agent of component (E) of the aqueous alkaline composition is selected from the group consisting of phosphates, cumene and toluene sulphonates, alkylbenzene sulphonates, alkane sulphonates, ester sulphonates, and phosphoric acid esters.